Bieler+Lang ExDetector HC 100 / HC 100 K — flammable gas detector, zone 1

A pellistor detector for flammable gases and vapours in zone 1 — where an explosive atmosphere may be present in normal operation. 0–100 % LEL, 4–20 mA output, SIL 1. In the HC 100 K version the head sits in the duct and withstands 80 °C.

Zone 1 — where the difference lies

Most fixed flammable-gas detectors are approved for zone 2, where an explosive atmosphere occurs only rarely and briefly. The HC 100 is also approved for zone 1, where an explosive mixture may appear during normal operation — above a tank, at a filling point, in a digester.

On top of that comes an EC type examination certificate to directive 2014/34/EU and a measurement function certificate BAM 03 ATEX 0003 X, so the detector enters SIL 1 rated systems without argument at handover.

The pellistor — what it measures and what it dislikes

Measurement is based on catalytic combustion: the gas oxidises on a heated bead, the heat changes its resistance, and that is converted into a percentage of the lower explosive limit. The advantage is breadth — one sensor covers a very long list of hydrocarbons and hydrogen.

The limitation matters too: a pellistor is poisoned by silicones, hydrogen sulphide and lead compounds. Where such substances are present in the atmosphere, the right choice is the ExDetector SC 220 with a semiconductor sensor.

HC 100 K — the duct version

The HC 100-T / HC 100-K combination was developed for measurement inside a duct or pipe network. The sensor head is separate from the transmitter and withstands up to 80 °C, while the electronics stay somewhere accessible and cool.

This is the answer where the air in the hall is not the point — what matters is what is actually flowing through the duct: dryers, extraction above tanks, process installations.

Calibration by one person

Adjustment is done directly at the sensor, with the Calibrationbox-i unit. There is no need for a second technician at the controller reading values — with detectors spread across a hall or mounted high up, that halves the man-hours of an inspection.

Technical data

Parameter	Value
Measuring principle	pellistor — catalytic combustion
Measuring range	0–100 % LEL (lower explosive limit)
Detectable gases	flammable gases and vapours, incl. hydrogen and hydrocarbons (others on request)
Zones	zone 1 and zone 2
Type examination	EC type examination certificate to directive 2014/34/EU
Measurement function certificate	BAM 03 ATEX 0003 X
Functional safety	SIL 1
Measuring signal	linear 4–20 mA
One-man calibration	yes — directly at the sensor, with the Calibrationbox-i unit
Connection	3-pole
Duct version HC 100 K	sensor head separate from the transmitter, rated to 80 °C
Manufactured in	Germany

Service with us

We are an authorised Bieler+Lang trade and service partner — we hold the manufacturer's written authorisation covering commissioning, maintenance and other service work, valid until 31 December 2028. Our technicians were trained in Achern and work with original parts and factory procedures.

In practice that means we commission, calibrate and service what we sell — nothing has to be shipped back to Germany. See our service scope or send equipment in.